Pilot support for reamers



May 24, 1932. G E MOE-N 1,859,836

PILOT SUPPORT FOR REAMERS Filed Oct. 1. 1929 Patented May 24, 1932 r PATENT 0mm GEORGE ELMER MQEN, OF KELSO, WASHINGTON PILOT sUrroR-r ron REAMERS Applicationfiled October 1, 1929. Serial No. 396,521.

This invention relates to improvements in reaming tools used for-reforming valve seats of internal combustion engines and pertains particularly to an improved pilot support or guide. 7

The primary object of the present invention is to provide in a reamer a'cutting tool carrying stem or post and a pilot therefor with a holder between the tool'carrying post and the pilot of such a character that the pilot may be raised or lowered as necessary to the proper performance of a reaming operation without it being necessary for the operator to alter the position of the'reamer.

In toolsof the character at present employed the pilot is used as a reamerholder and pilot combined." With this structure whenthe pilot is removed the reamer or'cutting tool must be dismounted therefrom. In the present invention this isdone away with as the pilot may be placed in or removed from position without removing the reamer from the machine.

A further object of the invention is to pro-' vide a pilot holder which will permit the necessary rotation of the reamer thereabout but will hold the pilot in such a manner that movement of thereamer and structure surrounding the pilot longitudinally on the pilot is prevented.

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with the understanding, however, that the invention is not confined to any strictconformity with the showing of the drawings but may be changed. or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawings Figure l is a view in longitudinal section of a reamer shaft showing the pilot support which forms a part thereof and a pilot in place therein.

Figure 2 is a transverse sectional view through the shaft and through one of the pilot hearings.

Referring more particularly to the draw- I ings wherein like numerals of reference indicate corresponding parts throughout the several views, the numeral 1 indicates generally a portion of a tool supporting arm adapted to be mounted upon the head of an en gine block for the support of the reamer tool. This arm may be of any suitable design for the proper support of the tool, such as the supporting arm illustrated in Patent No. 1,781,338, issued November 11th, 1930. I The arm 1 carries in a suitable manner at its outer end a sleeve 2 through which the reaming tool holding shaft 3 may be passed, this shaft being of tubular formation as shown;

This reamer carrying shaft is adjustably supported in an especially designed feeder indicated as a Whole by the numeral 4, which feeder structure forms the subject matter of my copending application, Serial No. 396,522, filed October 1st, 1929 and by means of which it is rotatably held in position upon the support 1.

A reaming tool 5 of any approved design is carried upon the lower end of the shaft 3 for operation upon the valve seat of a mo tor as indicated at 6.

Within the tubular shaft 3 adjacent the lower end thereof there is formed a centrally apertured partition 7 and threadably secured in this lower end of the tubular shaft between the partition 7 and the adjacent end thereof is a centrally apertured lower and removable partition 8. The partitions and 8 being in vertically spaced relation as shown. 1 v Held between the partitions 7 and 8 are two bearing races 9 the adjacent-faces of which are in abutting relation as shown and each of these races is centrally circumferentially split to form a pair of rings 10 the adjacent inner edges of which are cut away 'to provide the confronting bearing ball receiving grooves 11 which together form a lower ring 9 of each of the bearing races is provided with a suitable rib 15 to prevent the balls from rolling from position. These ribs do not, however, prevent the forcing of the balls into engagement with the pilot when the partition nut 8 is threaded inwardly to force the rings of the two bearing races together.

As is apparent the shifting of the partition nut 8 by means of which the bearing rings are held in assembled relation, inwardly toward the inner partition 7 will force the bearing rings together and this act-ion will tend to urge the bearing balls inwardly for tighter engagement with the pilot 13. In

": this manner any desired degree of pressure upon the pilot by the bearing balls may be had and this gripping of the pilot acts to prevent longitudinal movement thereof witl out interfering with the rotary movement r 'of the reamer shaft 3 while the tool is being used.

While the drawings show the use of the present bearing structure upon a pilot fixed in a valve stem guide so as to permit rotation of a rea-mer carrying shaft for the receding of the valve seat it is, of course, to

v be understood that this bearing structure may be employed for supporting a rotating pilot carrying a reamer upon its lower end for over sizing the valve stem guides. Also, it is to be understood that I do not wish to be limited to the specific form of bearing shown or to the particular number of bearing units shown in the drawings.

From the foregoing description it will be readily apparent that the pilot guide of the character herein described may be inexpensively constructed and when in use will tend to greatly expedite valve seat reaming operations because of the fact that the guide pilot for the tool may be withdrawn from one working position to permit the tool to be shifted to another working position without the necessity of removing the reamer or alterin the adjustment of the supporting shaft there or. c

Having thus described my invention, what I claim is V 1. In a tool of the character described, a tubular rotary tool carrying shaft, a partition disposed across the shaft adjacent one end and having a central aperture therethrough, a pair of bearing races in said tube, one of which is axially adjustable toward the other and one thereof resting against said partition, said races having confronting bearing ball receiving grooves near their inner peripheries, a centering post extending longitudinally through the shaft and passing through said races and the aperture in the partition, one of said grooves having the edge adjacent the post cut away whereby balls in the confronting grooves may move relative to the post, a row of bearing balls in said confronting grooves, and a member in n the shaft forcing said races together against the partition and crowding the balls inwardly from their grooves against the post.

2. In a tool of the character described, a tubular rotary tool carrying shaft, a partition disposed across the shaft adjacent one end and having a central aperture therethrough, a pair of bearing races in said tube, one of which is axially adjustable toward the other and one thereof resting against said partition, said races having confronting bearing ball receiving grooves near their inner peripheries, a centering post extending longitudinally through the shaft andipassing through said races and the aperture in the partition, one of said-grooves having the edge adjacent the post cut away whereby balls in the confronting grooves may move relative to the post, a row of bearing balls said confronting grooves, screw threads upon the interior of the shaft adjacent said partition, and a peripherally threaded plate in the shaft and engaging said threads for compressing said races against the partition to crowd the bearing balls therefrom against the shaft In testimony whereof I hereunto affix my signature.

GEORGE ELMER MOEN. 

